Currently available coating pans for medicament preparation include spray assemblies for applying coatings to tablets, for example, sugar coatings. See Accela-Cota.RTM. by Driamusa, Inc., Spartanburg, South Carolina; Hi-Coaters.RTM. by Vector/Freund; and Glatt-Coater.RTM. by Glatt Air Techniques, Inc., Ramsey, NJ. The spray arm assemblies of these devices represent the state of the art in coating technology, however, they are not without limitations.
The Accela-Cota.RTM. provides a spray collar which can be removed from the coating pan to facilitate cleaning and adjustments to the spray guns. The spray collar of this device appears to be hinged to the door of its housing and does not provide external adjustment means for adjusting the "spray distance", the distance between the nozzle and the pan, or the angle of the spray guns within the pan.
The Hi-Coaters.RTM. system from Vector/Freund provides a totally enclosed coating pan assembly having an internal spray arm. The manufacturer suggests that this device can be cleaned through the access door in the front of the unit. The Hi-Coater.RTM. system, therefore, does not provide a purge position for cleaning, and eliminating air from, spray nozzles and feeder hoses. Moreover, it does not provide external adjustment means for varying the spray distance, or spray angle.
The Glatt Coater.RTM. incorporates a "pull-out" nozzle arm which greatly assists maintenance of the spray nozzles. However, this device also lacks means for adjusting the angle and spray distance for the nozzles. In addition, this device does not suggest a method for externally purging the feeding lines and it is expected that such a procedure would be difficult to implement.
Accordingly, a need exists for a coating pan apparatus and spray arm assembly which permits adjustments to be made to the spray distance and the angle of the spray nozzles. There is also a need for a more flexible spray arm assembly which can enable facilitated maintenance and purging.